The Open UniversitySkip to content
 

Hydrogen Permeation Through Nickel And Nickel Alloys: Surface Reactions And Trapping

Altunoglu, Abdulkadir (1994). Hydrogen Permeation Through Nickel And Nickel Alloys: Surface Reactions And Trapping. PhD thesis The Open University.

Full text available as:
[img]
Preview
PDF (Version of Record) - Requires a PDF viewer such as GSview, Xpdf or Adobe Acrobat Reader
Download (5Mb)
Google Scholar: Look up in Google Scholar

Abstract

The frequency variations of attenuation and phase lag of the modulated gas flow through thin metal foils have characteristic features whether permeation is diffusion controlled, is influenced by surface reactions or affected by internal trapping.

Analysis of data obtained for hydrogen permeation through nickel show that hydrogen is dissociatively chemisorbed in nickel.

The permeation parameters diffusivity, permeability and surface reaction rate obtained for nickel are:

D/(m2s-1) = 7.12 x 1-7 exp [-4.64 x 103/RT/(K)]

Pm/(molH2m-1s-1Pa-1/2 = 3.35 x 10-7 exp[-54.25 x 103/RT/(K)]

Ksm/(molH2m-3Pa-1/2) = 0.47 exp[-13.6 x 103/RT/(K)]

K1/(molH2m-2s-1Pa-1) = 1.44 x 1-6 exp[-29.68 x 103/RT/(K)]

Where R=8314Jmol-1

The experiments conducted on cold-worked nickel have revealed that hydrogen is trapped within the bulk during the permeation in this material.

A series of experiments conducted on cold worked nickel+2% thoria has also revealed that hydrogen is trapped within the bulk during the permeation. Analysis of data obtained for cold worked nickel+2% thoria suggest that hydrogen is trapped at the dislocation networks around thoria particles.

Frequency variation of attenuation and phase lag of the modulated flow show that hydrogen trapping in both cold-worked nickel and nickel+2% thoria is in dynamic equilibrium. A trap depth of 40 kJ/mol has been obtained for nickel+2% thoria.

Item Type: Thesis (PhD)
Copyright Holders: 1994 The Author
Keywords: nickel alloys; hydrogen content of metals; absorption and adsorption of gases
Academic Unit/Department: Mathematics, Computing and Technology > Engineering & Innovation
Item ID: 19842
Depositing User: Ann McAloon
Date Deposited: 11 Feb 2010 12:04
Last Modified: 07 Oct 2014 09:25
URI: http://oro.open.ac.uk/id/eprint/19842
Share this page:

Actions (login may be required)

View Item
Report issue / request change

Policies | Disclaimer

© The Open University   + 44 (0)870 333 4340   general-enquiries@open.ac.uk